Recording air-pyrometer.



No. 659,616. Patented 0st. 9, |900. W. H. & E. H. BRISTOL.

RECORDING AIR PYROMETER.

(Application led May 24, 1900.)

(No Model.)

il ll will m BMM ATTQRNEY.

rre STATES ATENT OFFICE.

WILLIAM H. BRISTOL, OF HOBOKEN, NEW JERSEY, AND EDGAR I-I. BRISTOL, OF NAUGATUCK, CONNECTICUT, ASSIGNORS TO THE BRISTOL COMPANY,- OF WATERBURY, CONNECTICUT, AND NEW YORK, N.- Y.

l RECORDING AAIR-PYROIVIETER.

SPECIFICATION forming part Of Letters Patent NO. 659,616, dated. October 9, 1900.

Application filed May 24, 1900. Serial No. 17,846. (No model.)

To all whom, it may concern: a perspective view. Fig. 6 is a diagram illus- Be it known that we, WILLIAM H. BRISTOL, trating the principle involved. Fig. 7 is a residing at Hoboken, in the county of Huddiagram illustrating a modiiied form. son and State of New Jersey, and EDGAR H. Similar letters and numerals of reference 5 BRISTOL, residing at Na ugatuck,in the county designate corresponding parts throughout the of New Haven and State of Connecticut, citiseveral views of the drawings. zcns of the United States, have invented cer- Referring to the drawings, the letter A destain new and useful Improvements in Reignates the indicating tube or spring;,-B, the cording Air-Pyrometers, of which the followcompensating tube or spring; C, the bulb, 6o ro ing is a specification. made of a suitable refractory material, such Our invention has reference to improveas porcelain, and D the indicating or recordments in air-pyrometers, and has for its obing arm arranged opposite to a suitable chart ject to provide an instrument of this charor scale E. The tubes or springs A and B acter which will make a continuous record are substantially of the same construction as l5 upon a dial or chart and Which will render the tube or spring shown in our prior patent, unnecessary the corrections for barometer No. 514,256, dated February 6, 1894, each of and thermometer heretofore required to be the same consisting of a metallic tube of Hatmade in the reading of the instrumentwhen tened cross-section formed into a helix of, air-pyrometers of the usual known construcin this instance, three convolutions. By 7o zo tions were employed, thus eifecting saving 0f having a tube or spring of two or more comtime and labor, as the readings can be taken plete convolutions we are enabled to obtain directly from the instrument. sufcient movement at the free end of the To this end our invention consists, essentube or spring to dispense with multiplying tially, in the combination of an indicating devices intermediate of the tube or spring 25 tube or spring adapted to be turned axially and the indicating or recording arm, as either by variations of pressure in the air-bulb due one of the tubes or springs may be considerto changesin the temperature being measured ed a series of Bourdon tubes connected end and having one end attached to a base and to end to concur in action, and consequently a compensating tube or spring having one the combined movement of the component 8o 3o end placed in mechanical connection with the tubes or springs under pressure will be comfree end of the indicating tube or spring and municated to the freeend of the terminal or its other end in connection with the indicatstructure and impart to the same an axial roing or recording arm, said compensating tube tation thro ugh an angle corresponding subor spring being turned axially by variations stantially to the movement of the several 35 in atmospheric pressure and temperatures in convolutions taken collectively. This cona direction opposite to the movements of the struction being described and claimed in our indicating tube or spring under the same inprior patent referred to, we make no claim fluences and so influencing the position of to it in the present application, our invention the indicating or recording arm as to comrelating, essentially, to the manner of arrang- 9o 4o pensate for errors which would be due to ing and connecting the two tubes or springs barometric and thermometric changes. so that the tube or spring B will compensate The nature of our invention will best be unfor barometric and thermometric changes derstood when described in connection with where the indicating or recording part of the the accompanying drawings, in whichinstrument is located. The indicating tube 45 Figure l represents a sectional elevation of or spring A has its inner end attached to a an air-pyrometer embodying our invention. bracket l, by means of hard solder or other- Fig. 2 is a side elevation, on an enlarged wise, so as to form a perfectly air-tight joint, scale, of the indicating and compensating and to-said end is conducted a tube 2, having, tubes or springs and parts appertaining therea very tine bore. The other end of said tube roo 5o to. Fig. 3 is a longitudinal section thereof. is attached by means of a suitable air-tight Fig. 4 is an end view of the same. Fig. 5 is joint 8, Fig. l, to the bulb C. The free or pheric pressure.

front end of the tube or spring A is connected to the adjacent end of the compensating tube or spring B, as at 4; but there is absolutely no connection between the interior of the two tubes or springs. In a forwardly-extending arm 5 of the bracketl is formed a bearing for one end of a shaft 7, extending longitudinallyand centrally through the tubes or springs and having its opposite end rigidly secured in a hanger 6, attached to the rear end of the compensating tube or spring B. To the front end of this shaft is attached the indicating or recording arm D, and consequently the latter participates iu the movements of said shaft. It will now be seen that if the indicating tube or spring A is turned in either direction the compensating tube or spring B participates in such movements without exerting any retarding action on the indicating tube or spring, in View of the connection t between thel two tubes or springs and the connection of the outer tube or spring with the shaft 7, which causes said shaft to turn in its bearing in the arm 5. 'Ihe two tubes or springs are made of equal strength, and therefore the same internal or external pressure will produce the same an- In practice the air t gular movement in each. in the bulb C, the indicating tube or spring A, and the connecting-tube 2 is exhausted to a large degree and the air in the compensating tube or spring is almost exhausted for a purpose to be hereinafter described. The

air being almost exhausted from the bulb,

the latter when cold is subjected -exteriorly to nearly atmospheric pressure, which, however, has no tendency to crack a bulb of refractory material, such as porcelain. When the bulb is subjected to furnace temperatures, the small amount of air in the bulb expands and produces a pressure practically balancing the external pressure, and consequently relieves the bulb of strains when in its weakest condition.

To illustrate the operation of the instrument, let it be assumed that the air has been almost exhausted from the compensating tube or spring and that the barometer rises. Under such circumstances the indicating tube or spring A would turn toward the left of Fig. 5 if the compensating tube .or spring `were not present-that is, in the direction indicated by arrow l in said figure and in diagram, Fig. 6; but the compensating tube or spring B being present and tending to turn to the right of Fig. -that is, in the direction of arrow 2, Figs. 5 and G-through the same angle the effect of changes in atmospheric pressure is neutralized, and the position and indication of the indicating or recording arm is unaffected by the rise of atmospheric pressure. For like reasons there would be no movement of the indicating or recording arm when there is a fall in atmos- By not entirely exhausting the compensating tube or springB the same willcompensatealsoforthermometricchanges `the compensating tube` or spring tends to turn in the opposite direction. By leaving a calculated amount of air in the compensat' Y ing tube or spring B compensation can be made perfect for any change in atmospheric temperature when the bulb C is at a given average temperature. To explain this more fully, let it be assumed that the instrument is adjusted fora working temperature of 27,000c Fahrenheit. Then in that case we exhaust the air in the compensating tube or spring to such an extent that the internal pressure in said tube or spring will, be slightly less than the pressure in the indicating tube or spring, caused by the given temperature. Consequently, as the tubes or springs have equal angular motion for equal changes ot pressure, a change of temperature at the recording part will have no appreciable effect, and consequently the instrument will accurately record changes of temperature at the bulb.

lt is evident that instead of placing the tubes or springs A and B one within the other they may be arranged as shown in Fig. 6, where they are in line and connected mechanically end to end at 4, the end of the indicating tube or spring A being rigidly held in the bracket l and the free end of the compensating tube or spring B carrying the indicating or recording arm D. The tubes or springs A and B may also be arranged one above the other or side by side, as indicated diagrammatically in Fig. 7.

We do not wish to restrict ourselves to the,`

specific construction for the hollow movable -ICO parts herein described, as. it is evident'that other constructions possessing the same features and producing the same result could be substituted therefor, the essential feature of our invention being the compensation for changes in barometer and thermometer by influencing the position of the indicating or recording arm or other device for effecting an indication or record.

If desired, the shaft Zand its bearing may be omitted, as they are used merely for the purpose of steadying the tubes or springs, the indicating or recording arm in this case vbeing attached directly to the free end of the compensating tube or spring, as indicated in dotted lines in Fig. 2

1. An indicating or recording dev ice for airpyrometers comprising two tubes coiled in the same direction, of which the first tube is rigidly held at one end and has its other end attached to the adjacent end of the second tube; said tubes being thereby caused to turn axially in opposite directions by barometric or thermometric changes, an indicating or recording arm, and an operative connection between the free end of the second tube and said indicating or recording arm, substantially as described.

2. An indicatingorrecordingdeviceforairpyrometers comprising a coiled indicating- 't ube, a compensating tube coiled in the same direction as the indicating-tube and placed in mechanical connection with the free end of the same; said tubes being thereby caused to turn axially in opposite directions by barometric or thermometric changes, a connection between the bulb and the indicating-tube, and an indicating or recording arm placed in connection with the free end of the compensating tube, substantially as described.

S. In an air-pyrometer, the combination with a coiled indicating-tube having one end rigidly secured, a compensating tube coiled in the same direction as the indicating-tube and having one end attached to the adjacent end of the latter and its other end attached to and holding one end of a shaft, a support for the opposite end of the shaft, an indicating or recording arm attached to the shaft, a bulb, and a tube placing said bulb in communication with the indicating-tube at its fast end, substantially as described.

4c. In an air-pyrometer, the combination with a coiled indicating-tube having one end rigidly secured to a bracket, a compensating tube coiled in the same direction as the indicating-tube and having its adjacent end mechanically attached to the free end of the indicating-tube and its other end attached to and holding one end of a shaft extending through the tubes, an arm extending from the bracket and forming a bearing for the opposite end of the shaft, an indicating or recording arm attached to said shaft, a bulb, and a tube connecting the bulb with the fast end of the indicating-tube, substantially as described.

5. An indicating or recording device for airpyrometers comprising two tubes coiled in the same direction and one coil placed within the other, the first of said tubes being rigidly held at one end and having its other end in mechanical connection with the adjacent end of the second tube; whereby the tubes are adapted to turn axially in opposite directions under barometric or thermometric changes, an indicating or recording arm, and an operative connection between the latter and the free end of the second tube, substantially as described.

6. An air-pyromcter comprising two connected hollow parts coiled in the same direction and adapted to be aiected by barometric or thermometric changes to move in opposite directions for compensating for infiuence of such changes, a bulb placed in communication with one of the hollow parts, and an indicating or recording device influenced and operated by the movements of said parts, substantially as described.

7.A An air-pyrometer comprising two connected hollow parts coiled in the same direction and adapted to be aected lay-barometric or thermometric changes to move in opposite directions for the purpose of compensation, a bulb placed in communication with one of the hollow parts; said bulb and hollow parts being exhausted below atmospheric pressure, and an indicating or recording device intluenced and operated by the movements of said parts, substantially as described.

8. An air-pyrometeror the like having a bulb, an indicator,and a compensator formed by two connected hollow parts adapted to be affected by barometric or thermometric changes to move in opposite directions lfor the purpose of compensation, one of said hollow parts being placed in communication with the bulb, and the other hollow part being mechanically connected with the free end ot the first hollow part and carried by the same, substantially as described.

9. An air-pyrometer or the like having a bulb, an indicator, and a compensator formed by two tubes coiled in the same direction; one of said tubes being in communication with the bulb and mechanically connected with and carrying the other tube, substantially as described.

10. An air-pyrometer or the like having a bulb, an indicator,and a compensator formed 'by two tubes helically coiled in the samedirection; one of said tubes being in communication with the bulb and mechanically connected with and carrying the other tube, substantially as described.

l1. An air-pyrometer or the like having a bulb, an indicator, and a compensator formed by two coiled tubes,of which the rst tube is in communication with the bulb and the second tube is mechanically connected with the free end of the first tube and carried by said first tube, substantially as described.

In testimony whereof we have hereunto set our hands in the presence of two subscribing witnesses.

WILLIAM H. BRISTOL. EDGAR I-I. BRISTOL. Witnesses:

CEAS. W. BANBY, FRANKLIN B. BRISTOL.

IOO 

